In recent years, due to the depletion of fossil energy and environmental pollution caused by the use of the fossil energy, an interest in electric products that can be driven by secondary battery batteries is increasing. Accordingly, as the technology development and demand for a mobile device, an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), an energy storage system (ESS) an uninterruptible power supply (UPS) and the like increase, the demand of the secondary battery as an energy source is rapidly increasing.
The secondary battery has received public attention as a new energy source for promoting eco-friendly performance and energy efficiency in that byproducts are not generated at all according to the use of the energy as well as a primary advantage of dramatically reducing the use of the fossil energy.
In particular, the secondary batteries used in the electric vehicle, the hybrid vehicle, the energy storage system, and the uninterruptible power supply require characteristics of a high output and a large capacity and in order to maintain the characteristics, it is important to frequently measure and monitor voltages of the secondary batteries.
As a result, in the related art, a photo-MOS relay is connected between the secondary battery and a measurement unit and the voltage of the secondary battery is measured by controlling an operation state of the photo-MOS relay to an On state at the time when measuring the voltage of the secondary battery is required, but since a life-span of an internal light emitting diode (LED) is short, an available period of the photo-MOS relay is short and it is difficult to miniaturize the photo-MOS relay.
Therefore, the present inventor has invented a transformer relay and a battery voltage measurement system using the same, which transform voltage a voltage measurement signal transmitted from a controller by using a transformer and measure voltage of a battery by conducting a relay by inputting the voltage of a transformed voltage measurement signal in a measurement unit measuring the voltage of the battery and the relay that conducts or cuts off electrical connection of the battery in order to solve the problem.